Electrograph.



R. S. M. MITCHELL.

ELECTROGRAPH.

APPLICATION FILED MAR. 13, 1912.

1,077,361,, Patented Nov/1, 1913.

2 SHEETSSHEET 1.

N! YYVESSES 4 UNITED STATES PATENT orriou.

Rionmn s; m. m'rcnnmz, or suna'cusn, NEW YORK, ASSIGNOR, BY Dinner ANDMEsNn'AssIGNMENms; To THE TALKING MovING PICTURE 00., Inc, or'sYRAcUsE,NEW YORK,ACORPORATIO1\T or NEWYORK.

EEEEGTROGRAPH;

s ecification-oi Letters Patent; 7

Patented Nov. 45, 1913.

Application filed'March 13, 1912. Serial No. 683,593:

To all whom it may'concem Be-Pit known that I, RICHARD-S. MtMrrom Ema,-

citizew 0% the United States,- rel 1ding-at Syracuse, in the county ofOnondaga and State oi? New Yorlt;- have invented? ccr-.

. able record cylinder adapted for recordingimpressions effectedbyavibrating needle or stylus.

A further object is: toprovldea double screw-feeding mechanism forcontrolling the travel ott-he' stylus over the'sur-t'ace of saidcylinder. 7 i I A further object is'to provide a sensitive resilientadjusting mechanism for regulating the pressure of the stylnsupon thecylinder.

A further object is to=provide means for readily and accuratelyadjusting: and settingthe stylus forstarting the recording or thereproducing of a; record at a precisepoint, and for repeatedly startingtherecord from the same point;

A further object is to provide meansfor throwing and holding the'stylusout ot-engagement with; the record; cylinder, the said means beingcontrolled by an electromag net, and wherein by the deenergizingof thesaid magnetthe stylus retingagesthe record cylinder at. the point fixedby the said, adjust-ment.

A further object is-to provide means assooiated with the stylusforrecording electrio-finctuations given to it by an external current, andalso to reproduce an extra circuit those fluctuations in'tacsi'miile.

A1 further object isto provide means-for- =receiving at a distance thesounds of voices,

music and the'like, and thenchanging said sounds into electromagneticvibrations which are simultaneouslyimpressed by the said stylus; uponthe recordcylinder carried:

by, themaohine. I Aefurtherobjectis to. provide means for converting-1the impressions recorded upon the record cylinder intoelectro magneticvibrations whichcause fluctuations in a se-- ries of electric currentswhich operate asgraph; showing thetransmitter in. positionready' forreproducing a record. Fig; 2' is arear side elevation; showing thepartsin: the same position; also showing the starting and adjustingmechanism; Fig; 3'is adiagrammatic view;-. showing the primary andsecondary circuits in connection with the transmitter and receiver. Fig.4 is. avertical; longitudinal section through the re ceiuerg; showing aplain. diaphragm and a horn for amplifying sounds. Fig. 5 is a front endelevation and part section ;-show 'ing the receiver having a diaphragmwith stylus; also showing the starting mechanism held'in operativeposition by a magnet, the receiverbeing' tilted: for breaking the connection between the feeding parts. Fig. 6

.is a front end elevation andpart section;

showing the transmitter in the act of reproducing the-vibrations fromthe record. Fig. 7 is an enlarged detail; view showing the interlockingof the starting lever with. the guide sleeve of the carriage. Fig. 8 isan enlarged detail view taken on line 88 of Fig. 7 Fig. 9 is a bottomplan view of the base of the transmitter and receiver. Fig. 101-isanenlarged detail view of one of the spring electrodes, shown. in Fig. 6.Fig. 11 is a reduced sectional viewof the transmitter; showing a plaindiaphragm and a horn for receiving sound waves to be-recorded.

In the drawings, the frame of the machineconsists of three. independentsections or parts, as 2,3 and 4,; which are spaced apart, as shown.These sections support all of the working and other parts of themachine.

The bottoms of the frame sections are pro-' vided with flanges. 5, whichpreferably, rest upon a substantially level base, as 6, to

parts, may be secured in. any

which the. said suitable manner.

' by a similar belt 28.

7 represents a cylinder or drum, upon -'which may be telescopicallymounted a record cylinder or roll 8, which may be secured to the drumby. any suitable means, but is preferably held from turning on the drum,by means of a key 9, which is received by a corresponding key way,'which is formed in the inner surface of the tube 8. The record tube 8preferably comprises the same composite material as is usedin connectionwith the well-known talking-machines. The head-end of the drum 7 is pro-Vided with a circumferential flange 10, which corresponds in depth tothe thickness of the cylinder 8;

11 represents a groove or recess formed in the circumferential surfaceof the flange 10, and the said recess is preferably disposeddiametrically opposite the key 9. Under this arrangement, every recordtube may be repeatedly applied to the drum 7 in exactly the same manner.

The head-end of the drum 7 is provided with a relatively long integralgudgeon or shaft 12, which passes through central bearings 13 of thespaced frame sections 2 and 3. The bearings 13 are preferably split forreceiving detachable bushings 14, which are held in place by means ofclamping screws 15, which pierce depending lugs 16 and 16, the lug16being threaded in the usual man ner. The frame sections 2 and 3 arepreferably spaced apart a suflicient distance to support and hold thedrum 7 and the record tube in true horizontal position. The drum 7 isheld in place and prevented from longitudinal movement or play by a pairof sheaves-17 and 18, which are formed integrally with concentric hubs19, the said hubs filling the space between the frame sections 2 and 3,and are secured to the shaft 12 by means of a set-screw 20.

21 represents a stationary guide shaft or" rod, which pierces arms 22 ofthe frame sections 3 and 4, and the said shaft is held rigidly in placeby set-screws 23.

24 and -25 represent like wormor screw shafts, which are disposed aboveand on each side of the drum. 7. The worm shaft 24 is revolubly mountedin arms 26 of the frame sections 2, 3 and 4; while the worm 25 ismounted in bearings arranged in the arms 22 of the said frame sections.The worms 24 and 25 are provided with fine threads preferably 100 to 200to the inch-and the said worms are driven in the same direction, and atthe same speed, by means of sheaves 27' and 28, which are mountedrigidly on said shafts, between the frame sections 2 and 3. The sheave27 connects with the sheave 17 by means ofa flexible belt 27 the sheave28 connects with the sheave 18 All of the said sheaves are preferably ofthe same diameter, so that the drum and the two worm shafts may beturned by the same power synchronously. The shaft or gudgeon 12preferably extends beyond the frame section 2, and carries a drivingsheave 29, by means of which the drum and worms maybe driven by a commonpower. The sheaves 27 and 28 are made fast to the worm shafts bysetscrews 30.

The carriage of the machine is mounted above the drum 7 and the worms 24and 25, and consists of a metal ring or frame 31, circular in form,within which a receiver or transmitter is disposed and carried. At therear side, the carriage is supported by the guide shaft 21, by means ofa lug 32, which may be integrally formed with the ring 31.

The lug 32 is preferably formed eccentric relatively to the ring 31, andhas a sleeve 33 which is bored out to slidably fit the shaft 21, One endof the sleeve 33 is cutaway to provide a clutch-tooth 34. The

front side of the carriage is fitted with an angular bracket 35, whichis secured to the carriage by screws 35'. The lower arm of the bracket35 extends inwardly beneath the ring 31, and to its underside is secureda half nut 36, the free end of which is fashioned to fit and engage thethreads of the wprm 24. The arrangement of the parts 35 and 36 is suchthat, the forward side of the carriage is supported, while the machineis in operation, by the worm 24. 37 represents a second half nut orchaser, which is secured" to the underside of the sleeve 33 at the rearside of the carriage, by a screw 37.

The nut 37 is inverted, as compared with the rack 36, so that when themachine is operated, the nut 37 engages the underside of the worm 25.The carriage is moved longitudinally over the drum 7 by the operation ofworms 24' and 25. In practice the worms 24 and 25 and the drum 7 areonly operated in one direction, as indicated by the arrows in theseveral views, which causes the carriage to be moved from the front tothe rear end of the machine. To return the carriage to the head of themachine, which is always the starting point, the operator may take holdof the bracket 35 and lift the frame 31 until the nuts 36 and 37 and thestylus clear the worms and record' cylinder,

as shown inFig. 5. Then by sliding the parts 32-33 on the shaft 21, thecarriage may be readily and quickly brought to the position shown inFigs. 1 and 2. In this way the connection between the lug 32 and theshaft 21 serves as a hinge for the car-' riage.

In carrying out thefobjects of the present stylus or needle is locatedwith relation to the head end of the record tube 8 and the flange 10 ofthe drum 7. And I also provide a positive starting mechanism which willalways bring the stylus carried by the carriage to the same startingpoint on the record cylinder 8. The starting mechanism consists of thefollowing parts: 38 represents a depending lever or arm, the upper endof which is formed with a sleeve 39, which is journaled on the shaft 21.One end of the sleeve 39 is cut-away to provide a clutch-tooth 39, whichinterlocks with the tooth 34 of the sleeve 33 (see Figs. 1, 2, 5, 7 and8). The opposite end of the sleeve 39 bears against arm 22 of the framesection 3. When the carriage 31 and the lever 38 are in the positionshown in Figs. 1, 2, 5, 6, 7 and 8, the clutch-teeth 34 and 39 areinterlocked, and while in this position, the carriage may be elevated orlowered by shifting the lever 38 toward or from the drum 7. The carriagemay also be swung on the rod 21 independently of the lever 38, wheneverdesired, as indicated by the dotted lines in Fig. 8. The lower end ofthe lever 38 is pivoted to a plunger armature 40 of a magnet 41, by apin 40, so that the said lever is allowed a slight lateral movement orswing, as indicated by a comparison of Fig. 5 with Fig. 6. To eflect thestarting of the carriage from a definite or fixed point in relation tothe drum and the'record cylinder 8, I provide a bolt 42, which piercesthe lever 38 near its lower end. The bolt 42 has a head 42, which isnormally held against the rear side of lever 38 by arm 43 of abell-crank lever, which is controlled by a coil spring 44. The spring 44tends to hold the bolt 42 in the forwardly extending pos tion shown inFig. 6, and the said bolt is disposed directly in line with the recessor groove 11 of the flange 10.- Just before the machine is started, theoperator should press the lower end of the lever 38 toward the drum 7,until the pin 42 is forced back through said lever and compresses thespring 44. At the same time the lower arm 45 of the bell crank is tiltedupwardly and passes between and engages two contact clips or springs 46and 47 carried by the magnet 41. The clip 46 is connected by a wire 48to a battery 49; while the clip 47 is connected to one end 50 of themagnet coil; the other end of the said coil being connected with thebattery by a wire 51. WVhen the arm 45 of the bell-crank engages theclips 46 and 47, it closes the circuit through the magnet 41, and thelatter then draws the armature 4O inwardly, and holds the armature andalso the lever 38 in the position shown in Fig. 5. At the time the lever38 is manipulated, as described, owing to the interlocking of the clutch3439', the carriage 31 is tilted slightly, as shown in Fig.

5, which breaks the connections between the feeding parts comprising thenuts 36 and 37, and the worms 24 and 25,.and the car'- riage will remainstill. While the carriage and lever 38 are in the position shown in Fig.5, the power may be applied to the pulley or sheave 29 for starting therotation of the drum and worms. After the machine is started, it onlyrequires a partial turn of the drum 7 to bring the recess 11 around tothe point where the bolt 42 is pressing against the flange 10. When therecess 11 comes opposite the bolt 42, the latter being under pressure ofthe spring44, will shoot into the recess, thereby allowing spring 44 torelax or expand, which in turn will rock the bell-crank back to the restor idle position shown in Fig. 6, which will break the electricconnection at the clips or switch 4647 and deenergize the magnet 41.Instantly upon the breaking of the circuit the carriage will gravitateby its own Weight from the position shown in Fig. 5 to that shown inFig. 6, and at the same time lever 38, owing to the engagement of theclutchteeth 3439,' will be forced away from the drum 7. Then, if themachine continues to operate, by reason of the meshing of the racks 3'6and 37 with the worms 24 and 25, the carriage will be held in truehorizontal position, and will be moved from the head toward the tail ofthe machine, at a rate of speed governed by the number and fineness ofthe threads of the worms. If it is necessary to stop the carriage 31 atany time before it has traveled the full length of the drum 7, this maybe done by simply manipulating the lever 38 and thereby energizing themagnet 41. The power should be shut ofi at the same time that the lever38 is operated, so as to prevent the automatic starting of the carriage,as described.

The electric and associated parts carried by the machine will now bedescribed.

In the present device, the impressions or record which are recorded onthe cylinder 8, are made in the first instance by a stylus or needle 53,which is carried by a spider or holder 54, which is soldered orotherwise I ing or nonconducting material may be used for the purpose.The diaphragm 55 is disposed between the top 57 and the base 58, as bestseen in Fig. 5. A series of bolts 56 clamp and hold the sections 57 and58 together.

g The diaphragm 55 is vibrated by the fluctuations of an electriccurrent which i passes through a series of magnets, a, b, c and d, whichconnect to and depend from a steeLor iron ring 60, which is rigidlysupported in a chamber 61 of the cap 57, by a of the cap 57. When thediaphragm 55 is placed in operative position in the receiver, the spider54 and also the stylus 53 project slightly below the bottom part 58, sothat when the half nuts 36 and 37 engage the worms 24 and .25, the pointof the stylus 53 will be in engagement with the top surface of therecord cylinder 8 (see Fig. 6). When the receiver 56 is employed forrecording the vibrations on a blank record, the said receiver is placedwithin the circular carriage frame 31. The rear side of the receiverbeing secured, by one of the bolts 56 to an inwardly projecting part 65,which is pivoted or hinged to the bottom side of the frame 31 by a pin65'. The forward or opposite side of the receiver is adjustablysupported in the frame 31 by means of a bolt or rod 66, which passesthrough the top and bottom sections of the receiver and then upwardlythrough one arm of the bracket 35 and a coil spring 67, and the saidspring is held in place and given the desired tension by means of athumb-nut 67 The spring 67 imparts a slight resilience or flexibility tothe forward side of the receiver and permits of a fine adjustment of thestylus or needle 53 relative to the surface of the record cylinder 8.The electric current which energizes the. magnets a, b, c

jam-nuts 70. I. next and d is supplied by a pair of wires 72 and 73,which form parts of a secondary alternatin circuit which will later bedescribed.

Be ore a new record is made the operator should make a mark, as 68, onthe record cylinder 8, opposite the recess or groove 11 in the flange 10of the drum, the said mark is toindicate the point where the stylus 53shall begin the record, as indicated by the threads in Figs. 1 and 2.After he has made the'mark 68, he should then adjust the carriage 31, soas to bring the point of the stylus to said mark. To adjust thecarriage- 31 and receiver 56, I provide a lug 69 on the sleeve 33, throuh which a screw 69 is threaded, the said screw being locked and held inany desired position by means of rovide a similar lug 71 on the sleeve39 0 lever 38. The inner end of screw 69' engages the lug 71, whichserves as a stop for limiting the return movement of the carriage towardthe head of the machine. By the use of the screw 69, the carriage may beadjusted for setting the stylus exactly on the mark 68, or many otherposition desired. At the time the record is made on the cylinder 8,there are no sound waves received by the diaphragm 55, and no soundsuttered at or near the receiver 56, can enter the receiver or have anyefi'ectwhatever upon the diaphragm 53. Hence, no matter what sounds ornoises may be made in the vicinity-of the receiver 56, no record orimpression will be made upon the record cylinder 8. So far as therecording and transmitting of the record on the part 8 is concerned, themachine is entirely silent. 7 At the time the records are made, thesoundsof voices, music or other noises are made at a distance from themachine. These are received by a specially constructed transmitter towhich a horn is attached. ,Whatever impressions are made on the recordare effected entirely by electromagnetic vibrations, produced by thefluctuations in the electric currents or cir cuits, which are receivedthrough the wires '72 and 73, and transmitted by the magnets a, b, c andd to the diaphragm 55 and then to the stylus 53, which frictionallyengages the cylinder 8', and indents or otherwise formsimpressions whichcorrespond to said vibrations.

Fig. 6 illustrates a transmitter employed for reproducing the vibrationsor impressions recorded on the roll 8, which will now be described:Assuming that a record has already been made on the roll 8, as indicatedby the threads 8 in Figs. 1 and 2, and that the reproduction thereof isto be cffected, I place within the circular frame 31 of the carriage atransmitter 75, which comprises a solid back or cap 76 and 'a base 77.Both of these parts are preferably made of an insulating material, suchas hard rubber, fiber and the like. The parts 76 and 77 are circular, asshown. The top 76 is prefer,

ably hollow for providing a relatively large chamber 78, while thebottom 77 is provided with a shallow recess or depression 79, and afour-way slotted opening 80. Between the two sections of the transmitteris disposed a relatively large circular disk or diaphragm" 81, which maybe made of steel, wood -orcomposition, so long as it is suflicientlymetalicized to serve as an electromagnetic conductor. The diaphragm 81rests upon a narrow felt or like ring 82, which is disposed beneath itsedges. The said diaphragm is preferably held in place upon the felt,under the requisite amount of pressure, by a series of springs 83, whichalso serve as electrodes, and these are disposed at intervals around thetop side of the diaphragm 81. The springs 83 are held in place and givenmore or less tension as desired, by means of a series of bolts 84 andnuts 84', the, upper ends of the bolts 84 serving as binding posts. Tothe underside of the diaphragm 81 is secured a four-arm f spider 85,similar to the part 54 of the receiver, the outer ends of said armsbeing.

represents a stylus or needle which is con-- nected to the spider 85 inany suitable manner. The stylus 86 is preferably similar to thoseemployed on phonographs for reproducing the records. The spider 85 andstylus 86 preferably project slightly below the base 77, in position toreadily engage the record cylinder 8, when the carriage isin theoperative position shown in Figs. 1, 2 and 6. Upon the diaphragm '81 ismounted a series of hard rubber cups '87, each of which is glued orotherwise rigidly fastened to diaphragm 81, and the interior of saidcups are-filled with granulated carbon 88, which rests upon the topsurface of the diaphragm. The carbon 88 is subjected to a suitablepressure, by means of a series of screws or bolts 89, which are carriedby the top 76, thelower end of the screws being fitted with concavecone-shaped electrodes 90, which are arranged to exert an even pressureupon the carbon in the lateral and downward directions. The upper endsof the bolts 89 comprise binding-posts and these are fitted withadjusting nuts 89 and thumb-nuts 91, between which wires 92, 93, 94 and95 are connected. 96 represents a wire which connects in series with thehinding-posts 84 of thesprings 83. The four wires first named compriseseparate primary circuits having a common return throug wire 96 to thebatteries which are controlled by the transmitter 75. The transmitter 75is disposed in the carriage 31, in exactly the same manner as thereceiver 56, the rear side of the transmitter being secured to the hingemember 65, which is pivoted to the carriage by a pin The forward side ofthe transmitter is adjustably supported in the carriage frame 31 by avertically arranged bolt or rod 66, which passes through the rubberparts 76 and 77 and then extends upwardly and passes through one arm ofa bracket 35. The rod 66 is fitted with a coil spring 67, the lower endof which rests upon the bracket 35, while its upper end is engaged by athumb-nut 67 by means of which any desired tension may be given to thesaid spring for raising or lowering the transmitter relative to therecord roll 8 and also the carriage.

The circuits employed in connection with the receiver 56 and transmitter75 will now be described.

Referring to Fig. 3 the primarycircuits.

around the coils in a separate windings, as

consist of the four direct wires, 92, 93., 94

and 95, which pass in the form of a cable 97 toa box 98, in which isdisposed a series of. coils, illustrated diagrammatically at 99. Each ofthe four wires last referred to pass indicated, and then throughbatteries 92', 93,- 94' and 95 respectively. From the batteries, thesefour wires lead to and connect with a common return wire, which is thewire 96, and which connects in series the binding-posts 84. Under thisarrangement, each of the electrodes 89 is supplied with a direct currentthrough its own primary circuit, while the electrodes 8384 are connectedwith the common return wire 96. No matter whether the transmitter 7 5 isemployed for transmitting the sounds to the receiver 56 for recordingthe corresponding electro-magnetie vibrations on a blank recordcylinder, or whether it is employed for picking up the vibrations fromthe record and transmitting them to the receiver which reconverts thevibrations into sounds which are reproduced through a horn, aslOO, thetransmitter is always directly connected to the primary circuits, asdescribed. On the other hand, the receiver 56 is always connected withthe secondary circuit, which consists of the wires 72 and 73, which asdescribed, pass around the magnets a, b, 0 and d by means of a serieswinding, then to the binding-posts 63 and 64, thence to the four coils101, where the windings are arranged in parallel. Theelectro-motive-force induced in the secondary coils 101, is preferablyhigher than the primary electro-motiveforce, although this may be variedto suit conditions.

Fig. 4 represents the receiver 56, when the electric parts are employed,.(as illustrated in Fig. 3,) for reproducing a record of the vibrationswhich had previously been prepared, as described. The receiver shown inFig. '4, differs from the receiver shown in Fig. 5 in that the diaphragm53 has been substituted by a plain diaphragm 102, which is disposedbetween the rubber cap 56 and a modified base 103, which is provided.With a neck 104 for receiving and supporting the amplifying horn 100.The base 103 is provided with a clear concentric opening 105 whichafiords unobstructed commumcation with the diaphragm 102..

Under the'construction and arrangement of the electric circuits, asherein shown and described. both the receiving and the reproducing ofthe sounds may be effected at any reasonable or desired distance fromthe electrograp'h machine, by simply lengthening or 12 shortening thewires 72 and 73 of the secondary circuit. On the other hand, to make anew record, the transmitter 75 (see Fig.

11) is provided with a plain diaphragm 106, and a modified base 107 issubstituted for the base 77 to which the horn 108 may be conofconsiderably "heavier gage than the dia-t phragms of the commontelephone receivers and transmitters. The purpose of these modificationsis to prevent, as far as possible the vibration of the diaphragmsdirectly by any-sound waves whatever. In the present invention thediaphragm is only intended to be vibrated by the electro-magneticfluctuations in the currentwhich act upon magnets a, b, 0 and d. Thediaphragm 81 is only intended to be vibrated by the vibrations orpulsations it receives through the contact of the stylus 86 with therecord cylinder 8,

At the time a new record is made, the waves of the sounds of voices,music and the like, are carried by a born, as 108, to a plain diaphragm,as 106 which is placed in the transmitter 75, for the purpose. Thesewaves cause the diaphragm to vibrate, and the vibrations in turncause-an increase and decrease of the pressure between the fineparticles of the carbon 88, which will correspondingly increase anddecrease the resistance in the said carbon, thereby simultane ouslyincreasing and decreasing the current in the separate'circuit-s of theelectrodes 90, causing the said circuits to fluctuate synchronously withthe vibrations of the diaphragm. The fluctuations-of these currents inthe primary coils 99 induce like fluctuations in the secondary coils101, and are car-- ried by the wires 72-73 to the magnets a, b, c andaof the receiver 56, setting up magnetic fluctuations therein, which actupon the diaphragm armature 55, setting up in it vibrations. which arethen recorded upon a suitable blank record, like 8. To reproduce thesaid record, the order of the electric parts is reversed The transmitter75 is mounted in the carriage 31; and it is fitted with the diaphragm81; having the stylus 86. The stylus 86, when brought into contact withthe record cylinder 8, picks up the impressions which were recordedthereon, and

imparts them to the diaphragm 81, setting up therein vibrations orpulsations. The said vibrations or pulsations correspondingly increaseand decrease. the pressure upon the granulated carbon 88 confinedbetween said diaphragm and the cone-shaped electrodes 90. The increaseand decrease of multaneously fluctuations of the magnetic circuit,whitth will set up in the plain diaphragm 102 of the receiver vibrationscorresponding exactly to the vibrations set up in the diaphragm 81 ofthe transmitter, and

the sound Waves resulting therefrom will.

correspond absolutely to 'those received by the transmitter of therecording instrument and will be rendered audible bv the horn 100.

It is obvious that two or more receivers and horns may be connected tothe electrograph, for reproducing records at as many diflerent pointssimultaneously, and that some changes and modifications may be made inthe parts of the device, within the scope defined by the appendedclaims, without departing from the spirit of the invention.

Having thus described my invention, what I claim as new, and desire tosecure by Let- Patent, is

1. The combination of a frame, a rotatable drum supported by said frame,said drum having a circumferential groove and adapted to support arecord, a carriage reciprocable in said frame above said drum, atransmitter supported by said carriage and having a stylus adapted toengage said .rec- 0rd, a rocking lever carried by said frame, means forinterlocking said lever with said carriage, said lever capable of beingrocked by hand for tilting saidcarriage and transmitter away from therecord and drum, for stopping the playing of the record, a magnet, saidmagnet having an armature connected to said lever adapted when saidmagnet is energized to hold said carriage in the tilted position, and apin carried by said lever adapted to enter the groove of said drum fordeenergizing said magnet for allowing said caniage to gravitate towardsaid drum.

2. In combination, a rotatable drum adapted to carry a cylindricalrecord, a carriage mounted above said drum, means for moving saidcarriage from the head toward the tail of the drum, a rocking leveradapted to tilt said carriage away from the record cylinder,

an electro-magnet adapted for holding said' lever and said carriage. inthe tilted position, means carried by said drum, and means carried bysaid lever adapted to efiect the denergizing of said magnet for allowingsaid carriage to gravitate to the starting position. 1

3. In combination, a rotatable drum having a circumferential recess,said drum adapted to carry and operate a record, a carriage mountedabove and adapted to travel along said drum, a rocking lever adapted tolift said carriage away from said drum, a reciprocating pin carried bysaid lever, a magnet to hold said carriage in the elevated positionuntil said reciprocating pin engages the recess in said drum, and meanscontrolled by said reciprocating pin for efiecting the starting of saidcarriage at a fixed point on the record relative to the recess in saiddrum.

4. In combination, a frame, a rotatable drum supported by said frame,said drum having a circumferential notch, a carriage disposed above saiddrum, said carriage supporting a transmitter having a stylus adapted toengage a record carried by said drum, a lever pivoted in said frame,said lever having a pin adapted to engage the notch of said drum, saidlever capable of being operated by hand for lifting said carriage forbreaking the engagement of said stylus with the record and for bringingsaid pin into engagement with said drum, a magnet for holding saidcarriage and stylus in the inoperative position, and means for rotatingsaid drum so as to permit said pin to enter the notch in said drum forefii'ecting the lowering of the carriage and the engagement of thestylus with the record.

5. In an eletrograph, the combination with a frame and a rotatable drumadapted to support a record, said drum having a key for engaging akey-way in' the record, a carriage reciprocably mounted in frame, saidcarriage supporting a transmitter in position to engage the record, ashaft carriedby the frame upon which said carriage isslidable, a rockinglever, said lever journaled at one end on said shaft and having aclutch-portion adapted to engage a similar portion of the carriage,whereby said carriage is lifted away from the record when said lever isbrought toward said drum, an electro-magnet adapted when energized totemporarily hold said lever in said operated position, and means fordeenergizing said magnet for allowing said carriage to approach therecord for startingthe recording or reproducing.

In testimony whereof I afiix my signature in presence of two witnesses.

RICHARD S. M. MITCHELL. Witnesses:

HARRY DE WALLACE, ETHEL M. Jones.

said-

